Single-ion spectroscopy of four metastable-state clear-out transitions in Yb⁺ Isotope shifts and hyperfine structure

We present spectroscopic data for four metastable state clear-out transitions between 399 nm and 412 nm for all even long-lived isotopes of Yb+ as well as their hyperfine structure in ¹⁷¹Yb⁺. The strong ²⁢𝐷_3/2→¹⁢[1/2]_1/2 transition at 412 nm represents an attractive alternative for the standard 935 nm repumper used in cooling and trapping experiments, while the transition to the ³⁢[3/2]_3/2 state at 411 nm clears out the ²𝐹_7/2 state, for which typically 638 nm or 760 nm is used. These two alternative transitions simplify the experimental setup by removing the need for infrared optics to cool and manipulate Yb⁺ and may be of particular interest when considering integrated photonics solutions. We also present data for the transitions ²𝐷_3/2→³⁢[1/2]_3/2 at 399 nm and ²𝐷_3/2→¹⁢[5/2]_5/2 at 410 nm including decay branching ratios of the excited states.